Pycnoderma Grube, 1877

Salazar-Vallejo, Sergio I., 2011, Revision of Piromis Kinberg, 1867 and Pycnoderma Grube, 1877 (Polychaeta: Flabelligeridae), Zootaxa 2819, pp. 1-50 : 30-31

Key to species of Pycnoderma Grube, 1877

1 Tunic with few or no sediment grains; posterior neurospines entire............................................. 2

- Tunic covered by small sediment grains; posterior neurospines bifid, or bidentate.................................. 7

2(1) Tunic hyaline; chaetiger 1 with neurochaetae close to notochaetae; papillae thin, sparse, body rugose................... 3

- Tunic opaque; chaetiger 1 with neurochaetae clearly separated from notochaetae, as a lateral fan; papillae abundant, body pilose or pubescent.................................................................................... 4

3(2) Chaetigers 1–7 long, smooth; with three rows of elongate papillae................................... P. dannyi n. sp.

- Chaetigers 1–7 not markedly longer than following ones; with 6–8 irregular rows of tiny papillae.. P. congoense Grube, 1877

4(2) Cephalic cage chaetae as long as first 11–14 chaetigers; median notochaetae with many long articles, each about 7 times longer than wide........................................................................................... 5

- Cephalic cage chaetae as long as first 7–8 chaetigers......................................................... 6

5(4) Neurochaetae with two articles........................................... P. ferruginea ( Gallardo, 1968) n. comb.

- Neurochaetae with three articles, median one smaller........................................... P. escobarae n. sp.

6(4) Median notochaetae as long as body width..................................... P. glabra ( Treadwell, 1901) n. comb.

- Median notochaetae as long as 1/3 body width............................... P. talehsapensis ( Fauvel, 1932) n. comb.

7(1) First few chaetigers without dorsal lobes; sediment grains sparse, leaving wide tunic areas without sediment grains; first neurohooks from chaetiger 7; posterior neurospines bifid............................................... P. glasbyi n. sp.

- First few chaetigers with large dorsal lobes; sediment grains densely packed, completely covering the tunic; posterior neurospines bidentate.......................................................... P. gracilis ( Hartman, 1961) n. comb.